CEN th Lecture CEN 4021 Software Engineering II Instructor: Masoud Sadjadi Software Project Planning (POMA) Task Analysis

4 th LectureCEN 4021: Software Engineering II Acknowledgements  Dr. Onyeka Ezenwoye  Dr. Peter Clarke 2

4 th LectureCEN 4021: Software Engineering II Agenda  Software Project Planning (POMA) –Task Analysis  Work Breakdown Structure (WBS)

4 th LectureCEN 4021: Software Engineering II Work Breakdown Structure  Is a depiction of the project (model) in terms of the discrete pieces of work needed to complete the project and the ordering of those pieces of work.  Performed by software project team.  Focuses on the tasks required to produce the artifacts that are to be delivered.

4 th LectureCEN 4021: Software Engineering II Work Breakdown Structure  As the details of the software development and support process are realized subtasks are identified.  There are a number of tools used to support the WBS activity:  Graphical – MS Visio, Smartdraw, ArgoUML.  Scheduling – MS Project, Primavera TeamPlay

4 th LectureCEN 4021: Software Engineering II Work Breakdown Structure Steps in the WBS: 1.Examine the set of required external deliverables. 2.Identify and list the steps and tasks needed to produce the required deliverables, including intermediate deliverables. 3.Sequence the identified tasks required to produce the deliverable. 4.Estimate the effort required to perform each task. 5.Estimate the productivity of the resources that will be applied to the tasks.

4 th LectureCEN 4021: Software Engineering II Work Breakdown Structure Steps in the WBS: 6.Compute the time needed for each task by dividing the task effort estimates by the resource productivity estimates. 7.Lay out the time needed for each task and “label” each task with its task name and the assigned resources; this layout forms the initial schedule

4 th LectureCEN 4021: Software Engineering II Identify and list all deliverables For each deliverable: Identify and list the necessary tasks for completing the deliverable For each task: Compute the timeline required by dividing effort by productivity For each task: Estimate the productivity of the assigned resources For each task: Estimate the effort needed Sequence the tasks Lay out the timeline for all the ordered tasks need for each deliverable Perform task After the timelines for all tasks for all deliverable are computed Flow of WBS to schedule

4 th LectureCEN 4021: Software Engineering II WBS - Example  Deliverable 1: Executable code that is installable from a CD.  Deliverable 2: Help text, usage, and reference information that is installable from CD.  Deliverable 1 activities: –To develop code: requirements specification, and analysis (which are already completed), design, coding, and testing. –To make code installable: requirements specification (already completed), design, coding and testing

4 th LectureCEN 4021: Software Engineering II WBS - Example  Deliverable 2 activities: –Creating help text: requirements specification and analysis (already completed), design, writing, and testing. –Developing usage and reference information: requirements specification and analysis (already completed), design, writing, and testing.  Choice of activities and sequence depends on: 1.The size and complexity of both the problem and the solution,

4 th LectureCEN 4021: Software Engineering II WBS - Example 2.The process and methodology that the software organization has defined and trained its people to follow, and agreed with its client to use.  Sequencing the activities needed for the development of the artifacts can be a large problem for new software organizations.

4 th LectureCEN 4021: Software Engineering II WBS Task Refinement  List of activities for Deliverable 1: –Activity A: Designing and documenting the design using an agreed upon notation –Activity B: Coding (in language agreed upon) –Activity C: Defining test cases and generating test scripts –Activity D: Executing test scripts –Activity E: Correcting and fixing problems found during testing –Activity F: Collecting the tested executable modules and handing them to the packaging group

4 th LectureCEN 4021: Software Engineering II WBS Task Refinement Refinement of activity A: Table 2.1. Subtasks within the Design activity TasksDescription Task A-1Overall application, user interface (UI), and message architecture Task A-2Database and relational tables design Task A-3Application function 1 design Task A-4Application function 2 design Task A-5Application function 3 design

4 th LectureCEN 4021: Software Engineering II WBS - Task Sequencing  After the tasks refinement then comes the sequencing of the tasks.  There are usually dependencies between tasks i.e., Task A-1 needs to be completed before Tasks A-2, A-3, A-4 and A-5 commence.  There may also be overlap between tasks, i.e., Task A-2 maybe or may not be started before Task A-1 is completed.

4 th LectureCEN 4021: Software Engineering II WBS - Task Sequencing  Sequence diagrams depict the start-stop relationships among the various subtasks.  Sequence diagram – shows all the tasks required to complete an activity and the order in which those tasks must be performed, including the depiction of the tasks that may be performed in parallel.

4 th LectureCEN 4021: Software Engineering II WBS - Task Sequencing Task A-1 Task A-2 Task A-3 Task A-4 Task A-5 Fig. 2.2 Sequence diagram Tasks A-3, A-4, and A-5 maybe performed in parallel. Note there is no indication how task may overlap.

4 th LectureCEN 4021: Software Engineering II WBS - Task Sequencing  Steps for the construction of the software project: 1.List the deliverables. 2.For each deliverable, list the activities that are required. 3.For each activity, list the set of subtasks that are required. 4.Further refine any of the subtasks by creating the next level of subtasks, if necessary. 5.Construct the sequence relationship of the subtasks 6.Depict the sequence relationship with a sequence diagram

4 th LectureCEN 4021: Software Engineering II WBS – Time and Resource Assignments  What is a “satisfactory” level of refinement?  Guidelines: – Each task may be assigned to one person. –The estimate of the task cost, stated not in terms of money but rather in terms of time required to complete it, does not extend beyond more than two or three project status meeting.  Ensuring single person accountability makes the management and tracking of the task much easier.

4 th LectureCEN 4021: Software Engineering II WBS – Time and Resource Assignments  Assume that project management meetings are conducted very often, daily, for a small project (range of weeks) and weekly if the s/w project is large (range of months < 1 year). Units of tasks management:  Project team must decide on a unit of measurement, usually range from 1 hour units to a several days (< week).  It is important to state hours in a day and days in a week (5 or 7)

4 th LectureCEN 4021: Software Engineering II WBS - Time and Resource Assignments Units of tasks management:  Time must be allocated for non-direct-task-related activities e.g., departmental meetings, telephone interruptions etc.  How to estimate time required to complete a task. –Ask experienced s/w engineers (bottom-up estimating). –Assemble a team and ask them to estimate each task in terms of some common work volume unit e.g., lines of code (LOC) per hour per day

4 th LectureCEN 4021: Software Engineering II WBS - Time and Resource Assignments Units of tasks management: Example of Historical Information TasksPossible rates Requirements elicitation2 interviews/person-day Message design15 messages/person-day Code implementation2 functions points/person-day; 40 lines of Java/person-day Test generation5 test scenarios/person-day

4 th LectureCEN 4021: Software Engineering II WBS - Time and Resource Assignments Task A-1 Task A-2 Task A-3 Task A-4 Task A-5 End 5 days 3 days 7 days 5 days 2 days Fig2.3 Subtasks with estimated times. Longest path includes A-1, A-2, and A-3 (critical path) There is no slippage along the critical path.

4 th LectureCEN 4021: Software Engineering II WBS - Time and Resource Assignments Estimates and assignments:  Need to assign people to tasks. 1.Spmr need to consider skills required to perform each task, then seek people capable of performing these tasks. 2.Must consider the availability of the identified skilled people. 3.Must consider the timing of and the requirement of the identified person for another aspect of the project or another project. The above must be made in conjunction with the schedule in the time-estimated WBS.

4 th LectureCEN 4021: Software Engineering II WBS - Time and Resource Assignments Estimates and assignments cont:  The dependencies of the tasks in the WBS restrict assignment of resources, it also allows for the use of additional resources.  The skill of the team members may also restrict assignment.

4 th LectureCEN 4021: Software Engineering II WBS - Time and Resource Assignments Estimates and assignments: Subtasks with time Estimates and People Assignments SubtaskPersonSequence time-estimate A-1P1 A-2P2 A-3P3 A-4P4 A-5P5 5 days 3 days 7 days 2 days 5 days

4 th LectureCEN 4021: Software Engineering II WBS - Time and Resource Assignments Milestones SubtaskPersonSequence time-estimate A-1P1 A-2P2 A-3P3 A-4P4 A-5P5 5 days 3 days 7 days 2 days 5 days Minor MilestoneMilestone

4 th LectureCEN 4021: Software Engineering II WBS - Time and Resource Assignments Milestones:  End-point of a software process activity.  A significant event in a project that occurs at a specific point in time.  The labeling of a milestone gives a certain amount of priority and significance to the event.  Spmr may use the term “milestone” to emphasize the particular activity, as well as for the purpose of recognizing the attainment of a significant task.

4 th LectureCEN 4021: Software Engineering II WBS - Time and Resource Assignments Milestones:  Depending on the size of the project the schedule might only be depicted in terms of milestones. Such a schedule may be used by higher level management.  It is important for the spmr to recognize the accomplishments of milestones and publicly recognize them.  The spmr should also pay attention to missed milestones.